Mercruiser 496 - starter bolt hole threads gone !!

[sptjet90Reflexx]

So I figure this needs a helicoil.. But I am curious does anyone know if the 04 496 block threads go deeper than the factory start bolt is long? We just got our boat back a few weeks ago from the shop. It had a loose starter and the flywheel was all chewed up. It was under warranty through extended warranty (bought used) so it was no big deal.. Just took a few weeks to get her back. Well 3 weeks later same thing.. Went to go start her and grind the flywheel.. Checked the starter and it was wiggling by hand.. Took it back to the shop they tried to tighten it up and it just spun out all the threads..

As we all know this is the week of the 4th and we have 15 people coming from all over. Family we haven't seen in years. This boat was the toy for the week.. So does anyone know if a longer bolt will be a tempoary fix for the next few days? Then she will go back and have her motor pulled out AGAIN..

 

[Fun Times]

Hi there, To help with your starter bolt depth question, You might try calling one of the tech support experts over at Raylar Engineering @ (866) 496-8181. They work with the 496/8.1 engine models on a daily basis and may be able to let you know something on block to bolt depth.

http://www.raylarengineering.com/

Since the bolts keep coming loose, you may want to use a mirror and inspect the bolt holes on the engine "block" to make sure the block is not slightly cracked at the two holes. Also inspect the bolts for cracks or bent and are they OEM.

Also depending on the repair attempt, you might have better luck using a "wurth time sert" vs a helicoil for a better hold. Here's a short video on it if interested.

If the helicoil was already done than a time sert may not work due drilling size differences. Here's a short video to get you familiar with the time sert if interested.

http://www.youtube.com/watch?v=HP7bUxU1290

Hope your able to get your boat running in time, good luck.

 

[aerobat]

be very careful ! a friend learned the bolts the hard way with a 5.7 . he had loose starter bolts and was not able to figure out how this happens. one day the starter failed - he tries to pull the starter and sees one bolt is sheared off ! in a marine application this means you can pull the engine to repair that...

my last knowledge on that is that the marine starter bolts are shorter than the automotive and you have to use them. when not you deal with loose bolts. its then a question of time when engine vibrations and starter torque shear off the bolt when its only loose and the starter can "move".

 

[Bondo]

So does anyone know if a longer bolt will be a tempoary fix for the next few days?

Ayuh,.... The odds are very slim, to None,....

 

[sptjet90Reflexx]

Just to update this thread...

A longer bolt did work out. Turns out the previous owner had put a bolt that was not long enough in. However my starter tore up another flywheel and now I believe that this motor will require a shim. The process to pull the motor has begun again.

 

[sptjet90Reflexx]

Well.. The starter and flywheel are stripped out again and my boat has been sitting at the shop for almost 2 months waiting for them to pull the motor again. They say it needs a new long block because they claim that "Reversion" caused the starter bolts to deform and now the starter will not align anymore. I have never had a reversion problem on this motor as long as I have had it. I guess its possible the previous owner was an idiot but I dont know for sure.

Any thoughts?